Path Traversal in github.com/filebrowser/filebrowser/v2 (CVE-2026-55667)
Summary
Path traversal in github.com/filebrowser/filebrowser/v2 (CVE-2026-55667). Data can be tampered with by attackers. Exploitable via GET /api/raw/link/secret.txt. Mitigation: upgrade to 2.63.16 or later.
Original description
The description as published by the source.
File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.63.16, a scoped, non-admin File Browser user holding only the Create permission can delete arbitrary files outside their scope (other tenants' data, and the application's own database) via the upload failure-cleanup path. ScopedFs.RemoveAll is the one dereferencing operation that skips the symlink guard every other method enforces. The direct-upload handler runs RemoveAll on the user-controlled path during failed-upload cleanup, gated only by Perm.Create. If an escaping directory symlink already exists inside the user's scope, an authenticated create-only user can delete an out-of-scope target, bypassing both the ScopedFs boundary and the Perm.Delete gate. This vulnerability is fixed in 2.63.16.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-55667 has been found in github.com/filebrowser/filebrowser/v2.
Attackers can target a specific entry point like GET /api/raw/link/secret.txt over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 8.2/10.
What to do: upgrade github.com/filebrowser/filebrowser/v2 to 2.63.16 or later.
If unsure, ask your IT team or search "github.com/filebrowser/filebrowser/v2 CVE-2026-55667" on the vendor's site.
CVE-2026-55667 (github.com/filebrowser/filebrowser/v2) — CWE-22 / CVSS v3 8.2
Attack vector: remote (network-reachable) / no user interaction
Attack surface: GET /api/raw/link/secret.txt / POST /api/resources/link/secret.txt / ScopedFs / ScopedFs.RemoveAll
Patched: 2.63.16 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Path traversal (CWE-22) exists in github.com/filebrowser/filebrowser/v2. Attackers reach the vulnerable code path via GET /api/raw/link/secret.txt.
Check the vendor advisory for the affected versions of github.com/filebrowser/filebrowser/v2. Attack surface: GET /api/raw/link/secret.txt / POST /api/resources/link/secret.txt / ScopedFs / ScopedFs.RemoveAll.
Severity: High (CVSS 8.2/10). Data can be tampered with by attackers.
Update to 2.63.16.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/raw/link/secret.txt requests with malformed payloads or SQL meta-characters. Run grep -r 'github.com/filebrowser/filebrowser/v2' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/filebrowser/filebrowser/v2' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/filebrowser/filebrowser/v2を grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'GET /api/raw/link/secret.txt' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/raw/link/secret.txtへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade github.com/filebrowser/filebrowser/v2 to 2.63.16ステージング環境で 2.63.16 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against GET /api/raw/link/secret.txt on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com
- web github.com